| 1 |
A quality of raw water is improved by |
- A. Reduction
- B. Aeration
- C. Dehydration
- D. Incineration
|
| 2 |
Water will be considered polluted if it has dissolved oxygen. |
- A. 3ppm
- B. 4ppm
- C. 5ppm
- D. 6 ppm
|
| 3 |
Thickness of the atmosphere is |
- A. 100 km
- B. 500 km
- C. 1000 km
- D. 1500 km
|
| 4 |
Which is a secondary pollutant |
- A. Carbonic acid
- B. CO<sub>2</sub>
- C. SO<sub>2</sub>
- D. CO
|
| 5 |
Peroxyacetyl nitrate (PAN) is a irritant to human beings and it affects |
- A. Eyes
- B. Ears
- C. Stomach
- D. Nose
|
| 6 |
The avoid the formation of toxic compounds with chlorine which substance is used for disinfecting water |
- A. KMnO<sub>4</sub>
- B. O<sub>3</sub>
- C. Alums
- D. Chloramines
|
| 7 |
The residence time of NO is |
- A. Few hours
- B. 1 day
- C. 3 days
- D. 4 days
|
| 8 |
In which layer of atmosphere, ozone is present. |
- A. Thermosphere
- B. Mesosphere
- C. Stratosphere
- D. Troposphere
|
| 9 |
A single chloride free radical can destroy how many ozone molecules. |
- A. 100
- B. 100000
- C. 10000
- D. 10
|
| 10 |
The thickness of ozone layer is. |
- A. 25 to 50 km
- B. 25 to 28 km
- C. 3 km only
- D. 1 km only
|